It is an almost-exclusively male caucus.
It is deemed extreme far-right even by the House Republican leadership.
It was conceived in the dying gasp of the Tea Party movement.
They have repeatedly pushed for the defunding of Planned Parenthood.
They were considered the main reason for John Boehner's stepping down as Speaker of the House.
They are so difficult to work with that they may have single-handedly derailed Republican efforts to repeal and replace Obamacare, prompting even President Trump to take to chastise them in several tweets.
When founding member Justin Amash called for the impeachment of President Trump, they formally condemned him in a public statement. Amash stepped down the following month.

Why they might not be annoying

They are committed to their ideals and principles.
It was started by members of Congress fed up with 'business as usual.'
Its members on average tend to be comparatively younger representatives.
Its members have been known to spend more time in their own districts than their D.C. Establishment counterparts.
They allegedly choose to convene in the basement of a D.C. bar as opposed to the Capitol.
They proved to be a bigger headache for their own party than for the Democrat House leadership.
Despite being extremely combative, its members actually seem to like each other personally.